Reprinted from " The Entomologist's Monthlt/ Magazine," Vol. xxv.] 



September, 1888.] 77 



DESCRIPTIOX OF THE ASIl-CAULIFLOWER GNAT. 



BY R. II. MEADE. 



DiPLOSIS FRAXINELLA, Sp. 11. 



Cecidomyia minnta ? , Winnertz. 



Flava, thorace nigro-striato ; abdomine basi-nigro ; halteribus albis,amplisque ; 

 alis, vents cttbitalibus prope apicibus exeuntibus. Long. $ et '^ % mm. 



Head black ; palpi and proboscis pale yellow ; face with a tuft of white hairs ; 

 antennae in male about one and a half times the length of the insect, consisting of 

 2 basal joints which are yellow and sessile, and of 24 nioniliforni pedieelled ones, of 

 a pale brown colour, verticellated with white hairs ; the stalks are about as long as 

 the joints : in the female the antenna? are nearly as long as the body without the 

 oviduct, and consist of 2 basal joints as in the male, and of 12 ovoid very shortly 

 pedieelled others, to which a minute, tapering, terminal one is added. 



Thorax brownish-yellow, marked with three longitudinal brownish-black stripes, 

 which are almost confluent in the male, so that the dorsum looks nearly black ; 

 in the female tlie middle stripe is broad, while the lateral ones are very narrow. 



Abdomen yellow, clothed with white hairs, and having the base blackened; the 

 black part is more distinct in the female than in the male, especially upon the upper- 

 surface ; forceps of male large and yellow ; oviduct of female wanting.* 



Halteres lai'ge and white. 



Wings clothed with dark hairs; second longitudinal or cubital vein almost 

 straight until it nears the extremity, when it curves rather suddenly down ; and 

 reaches the border apparently slightly before the apex ; anal vein very indistinct. 



Legs with trochanters very pale, the other joints are clothed upon their upper- 

 sides with black hairs, which are most numerous upon the tarsi, which look darker 

 than the rest of the legs; the under-surfaces are furnished with white hairs, so that 

 the legs look white beneath. 



This very minute Cecid is probablj' the same as the one described 

 by AV'innei-tz under the name of C. minuta. It is rather an anomalous 

 species, for though the antennae are full}^ characteristic of the genus 

 Diplosis, Lw., the direction of the cubital vein more resembles that of 

 Cecidomyia, the point terminating apparently a little before the apex 

 of the wing. Winnertz only knew the male of his C. minuta, and was 

 ignorant of its life-history ; it also differed according to his descrip- 

 tion from the male of the ash-gall Diplosis, by having the antennae 

 twice as long as the body, and the points of the forceps black ; I have, 

 therefore, thought it better to describe it as a new species, giving it a 

 characteristic name. 



Like some other species of Diplosis this one lives as an inquiline 

 in the cauliflower ash-gall, -nhere it was found by Dr. Chapman, in 

 August, 1887, along with the larvae of Fniys riistica, and was kindly 

 sent by him to me for identification. 

 Bradford, Torks : August, 1888. 



* The only two specimens which I received were dried, in which state the male organs 

 cannot be fully described. 



